TOPS™ 3-Up 1099 Envelopes hold the new 1099-NEC and other IRS forms. TOPS™ tax envelopes have a security tint and pattern to obscure confidential information. Double windows fit NEC forms precisely so private information stays concealed. A cost-effective gummed closure provides a durable seal. Preprinted with "Important Tax Return Document Enclosed.". Seam Type: Side; Flap Type: Commercial; Trade Size: #8 5/8; Security Tinted: Yes.